In Beyond 3rd Generation/4th Generation (B3G/4G) wireless communication systems, the coordinated multi-point transmission (CoMP) technology has become an important direction in improving the overall cell performance and the performance of the edge users of the cell. In a CoMP system, a network node includes an Evolved NodeB (eNB) and an Access point (AP). Each eNB manages one or more cells, and one or more APs may scatter in each cell in a centralized or distributed form. The eNB establishes a connection with User Equipment (UE), manages the UE, and communicates with the UE through the AP.
In the CoMP system, one UE may be served by multiple cells at the same time; these cells may be managed by the same eNB, or may be managed by different eNBs. These cells are classified into main cells (serving cell) and auxiliary cells (cooperative cell), the main cells provide basic services and centralized services for the UE, and the auxiliary cells provide enhanced services and distributed services for the UE.
The fading conditions for the wireless transmission channels from the network nodes to the UE in different cells are independent from one another. In order to achieve larger scheduling gain, the system allocates the frequency resources and adjusts the links adaptively according to the frequency selection of the wireless channels, thus producing, for each cell, dedicated scheduling information specific to the cell. The scheduling information of the multiple cells serving the UE all needs to be sent to the UE. Upon the receipt of the scheduling information, the UE sends or receives data on specified wireless resources according to the information, thereby accomplishing the communication with the eNB. The scheduling information all needs to be transmitted to the UE through a downlink control channel.
However, in existing systems, when one cell is serving the UE, the cell has to send its scheduling information to the UE through its own downlink control channel. The downlink control channel only comprises therein the scheduling information for the cell, without the scheduling information for neighboring cells. However, when multiple cells are serving one UE, the differences between the channel conditions from the APs in the cells to the UE determine the parameter setting and transmission quality of the downlink control channels from the cells to the UE. When the channel condition is relatively poor, it is desired to use more wireless resources, such as frequency band, time slot, and power, to obtain a certain satisfying receiving effect, thus resulting in a reduction of resource efficiency.